Generally, Universal Serial Bus (USB) is a serial bus standard to the PC architecture with a focus on computer interface, consumer and productivity applications. The existing Universal Serial Bus (USB) interconnects have the attributes of plug-and-play and ease of use by end users. Now, as technology innovation marches forward, new kinds of devices, media formats and large inexpensive storage are converging. They require significantly more bus bandwidth to maintain the interactive experience that users have come to expect. In addition, the demand of a higher performance between the PC and the sophisticated peripheral is increasing. The transmission rate of USB 2.0 is not sufficient. As a consequence, faster serial bus interfaces, USB 3.0, are developed, which may provide a higher transmission rate so as to satisfy the need of a variety devices.
With the continued and expected long-term success of the USB interface, there exists a need to adapt USB to serve newer computing platforms and devices as they trend toward to smaller, thinner, and lighter form factors. In some cases, when electrical connectors are made smaller, the conductive contacts or pins of electrical connectors are brought closer to each other thereby increasing the electromagnetic coupling between the electrical connectors. An increase in electromagnetic coupling may generate unwanted noise or crosstalk that negatively affects the performance of the electrical connector. One particular concern regarding electrical connector is to reduce electromagnetic interference (EMI) so as to meet the relevant EMI regulations. There is a need not only to minimize the EMI of electrical connectors but also to contain the EMI of the host system in which the electrical connector assembly is mounted, regardless of whether a plug connector is plugged into a receptacle connector. In conventional designs, EMI shielding is achieved using the metal shell. However, due to increasing the speed rate of signals being transmitted through the electrical connector assemblies when a plug connector is plugged into a receptacle connector, the EMI shielding provided by conventional shell is proving to be inadequate.
In addition, in order to accommodate end users with the attribute of usability, durability, and robustness of USB connectors and also meet the requirement of the connector insertion force lower than extraction force when inserting a plug connector into a receptacle connector or extracting a plug connector from a receptacle connector, the existing USB connectors could not meet all above-mentioned requirements.